JERUSALEM – Images of ultra-Orthodox Jews dressing up as Nazi concentration camp inmates during a protest drew widespread condemnation Sunday and added a new twist to a simmering battle over growing extremism in Israel’s insular ultra-Orthodox community.

Religious extremists are facing increasing criticism for their efforts to separate men and women in public spaces, and Saturday’s protest, in which a child mimicked an iconic photo of a terrified Jewish boy in the Warsaw Ghetto, added to the outrage.

Thousands of ultra-Orthodox Jews gathered Saturday night in Jerusalem to protest what they say is a nationwide campaign directed against their lifestyle.

The protesters called Israeli police officers Nazis, wore yellow Star of David patches with the word “Jude” — German for Jew — dressed their children in striped black-and-white uniforms associated with Nazi concentration camps and transported them in the back of a truck.

Israel’s Yad Vashem Holocaust memorial denounced the use of Nazi imagery as “disgraceful,” and several other survivors’ groups and politicians condemned the acts.

“We must leave the Holocaust and its symbols outside the arguments in Israeli society,” said Moshe Zanbar, chairman of the main umbrella group for Holocaust survivors in Israel. “This harms the memory of the Holocaust.”

Six million Jews were killed by German Nazis and their collaborators during World War II. About 200,000 aging survivors of the Holocaust live in Israel.

Ultra-Orthodox Jews make up 10 percent of Israel’s population. In the past, they have generally confined their strict lifestyle to their own neighborhoods. But they have become increasingly aggressive in trying to impose their ways on others, as their population has grown and spread to new areas.

Extremist sects within the ultra-Orthodox community have been under fire of late for their attempts to ban mixing of the sexes on buses, sidewalks and other public spaces.

In one city, extremists jeered and spit at girls walking to school, saying they were dressed immodestly. They’ve also battled with police over street signs calling for segregation and attacked journalists who have covered their neighborhoods. In recent weeks, a few young Israeli women have caused nationwide uproars by refusing the orders of religious men to move to the back of public buses.

These practices, albeit by a fringe sect, have unleashed a backlash against the ultra-Orthodox in general, the climax of which came last week in a large demonstration where protesters held signs reading, “Free Israel from religious coercion” and “Stop Israel from becoming Iran.”

Rabbi Yitzhak Weiss, an organizer of Saturday’s protest, said the use of Nazi symbols was intentional and aimed at highlighting what he said was a campaign by the secular media against his community.

“The idea was to convey a clear and simple message: that wild incitement against the ultra-Orthodox community will not be tolerated,” he told The Associated Press. “The Israeli media’s incitement is reminiscent of the German media’s before World War II.”

One protester, Yaakov Israel, told Channel 2 TV that his community feels “persecuted” by the Israeli establishment. “What is being done to us here is a spiritual Holocaust,” he said.

It’s not the first time ultra-Orthodox zealots have referred to the Holocaust in their political struggles. But the sight of children dressed in garb that conjures up images of the darkest period in Jewish history was unprecedented.

Israeli leaders condemned the display and called on the ultra-Orthodox leadership to speak out against it.

The American Gathering of Holocaust Survivors and their Descendants, an umbrella organization of U.S. survivors, expressed its “utter contempt at this disgraceful exploitation” of the Nazi symbols.